Let's roll up our sleeves and solve this. We have 857 and we're going to multiply it by 4, essentially adding 857 to itself 4 times.
Step 1: 0 + 857 = 857
Step 2: 857 + 857 = 1714
Step 3: 1714 + 857 = 2571
Step 4: 2571 + 857 = 3428

So, 857*4 = 3428